Table 2. Empirical results.
|
Model 1
Baseline |
Model 2+
Main effect |
Model 3+
Interaction effect |
|
|---|---|---|---|
| Intercept |
-1.082*** (0.012) |
-1.071*** (0.012) |
-1.010*** (0.015) |
| Main effect | |||
| Recent average reward gain |
0.188*** (0.009) |
0.145*** (0.011) |
|
| Contribution frequency |
0.223*** (0.020) |
0.149** (0.033) |
|
| Contribution frequency^2 |
-0.173*** (0.020) |
-0.236** (0.064) |
|
| Moderating effect | |||
| Past accumulated experience |
0.335*** (0.022) |
||
| Recent reward gain * Past accumulated experience |
-0.074*** (0.009) |
||
| Contribution frequency * Past accumulated experience |
-0.152*** (0.016) |
||
| Contribution frequency ^2 * Past accumulated experience |
0.110*** (0.020) |
||
| Control | |||
| seeker’s status |
0.025*** (0.008) |
0.024*** (0.008) |
0.023*** (0.008) |
| question length |
-0.032*** (0.009) |
-0.034*** (0.009) |
-0.035*** (0.009) |
| answer length |
0.081*** (0.009) |
0.067*** (0.008) |
0.062*** (0.009) |
| presence of code |
0.459*** (0.016) |
0.436*** (0.016) |
0.449*** (0.017) |
| number of external references (URLs) |
0.113*** (0.009) |
0.097*** (0.009) |
0.095*** (0.009) |
| days to answer |
-0.608*** (0.019) |
-0.541*** (0.019) |
-0.521*** (0.019) |
| Log-likelihood | -43672 | -43302 | -43182 |
| X2 (model improvement #) | 739.58*** | 239.79*** | |
| AIC | 87357.64 | 86624.06 | 86392.27 |
| BIC | 87422.02 | 86716.04 | 86521.04 |
| N | 72959 | 72959 | 72959 |
Signif. codes: 0 ’***’ 0.001
’**’ 0.01
’*’ 0.05 ’.’ 0.1 ’ ’ 1
#Likelihood ratio test statistic